What does code P2AFF mean?

Q: What does code P2AFF mean?

Engine Coolant Temperature Sensor 4 Circuit High. P2AFF means the engine control module (ECM) has detected an abnormally high voltage on the signal circuit of engine coolant temperature sensor 4, which is a secondary temperature sensor used on some vehicles for monitoring a specific coolant path or component. The ECM expects a voltage within a calibrated range that corresponds to a plausible coolant temperature, and a sustained high voltage tells the module that the circuit is open, shorted to voltage, or that the sensor's internal resistance has risen beyond the expected limit.

DTC codes / P2Axx · Hybrid propulsion / P2AFF

P2AFFEngine Coolant Temperature Sensor 4 Circuit High

P2AFF means the engine control module (ECM) has detected an abnormally high voltage on the signal circuit of engine coolant temperature sensor 4, which is a secondary temperature sensor used on some vehicles for monitoring a specific coolant path or component. The ECM expects a voltage within a calibrated range that corresponds to a plausible coolant temperature, and a sustained high voltage tells the module that the circuit is open, shorted to voltage, or that the sensor's internal resistance has risen beyond the expected limit.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaHybrid propulsion

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.